Mineral Nutrition & Metabolism

1. Mineral Nutrition & Metabolism NUTR/POSC 650 NUTR 450 E.D. Harris eharris@tamu.edu

2. Nutrition and Metabolism of Minerals Objective of course: To deepen a students understanding of the role of minerals in living systems. To explore their multitude of functions. To learn how the chemical property of a mineral relates to its function in cells and tissues. To rationalize the consequences of mineral deficiencies based on their known functions. To gain some insight into experimental approaches used to assess minerals in a living environment The course will combine formal lectures, research literature, and interactive discussion. Formal lecture will cover elements in the syllabus. Didactic and interactive instruction will involve questions and discussions of formalized lectures in an environment where all students are both instructors and learners. Research literature will feature outside reading assignments of important papers in mineral nutrition. Instruction:

3. Web Address http://tamu.edu/classes/eharris/NUTR 650-489/ Lecture slides Class notes textbook chapters old exams study guides syllabus

4. Expectations: The student is expected to demonstrate a strong grasp of the fundamentals of mineral nutrition: to be able to relate the scope of mineral functions with chemical properties of minerals; to know how biological transport, uptake, and cell concentration of minerals is controlled; to know experimental approaches to studies of mineral functions. The course will NOT: Require students to memorize mineral RDAs, GRASs or DRIs for humans or any particular plant or animal species; to know the amount of a particular mineral in a food source; to know the toxic properties related to mineral excesses; The course will: Require students in a practical way to know determinants of bioavailability of important minerals, distinguish between macro and trace elements, to know at least 5 important functions performed by any one mineral element, and to know the biochemical bases of at least 3 deficiency signs for each mineral element.

5. Student Participation • Each student must give a report to the class on the topic “my favorite minerals”. The student will have the opportunity to research two minerals and give a report on the following: • Name of mineral element • Estimated requirement in humans or animals • Chemical properties most suited to its function • Chemical form most commonly found in a living system • Route of assimilation into body organs • Best dietary source • Functions performed by the mineral • Experimental procedures used to study the mineral • Potential candidates for interaction • System or systems most grossly affected by a deficiency • Symptoms of mineral deficiency • Further research needed

6. Attendance: Due to the contribution each student makes to the overall instruction in the course, attendance will be mandatory. Students who miss a class must provide the instructor with a written excuse for the absence. The absence must conform to what the university recognizes as a legitimate excused absence. There will be no opportunities to make up classes. The first class missed with no excuse will result in a 10 point deduction. The second 20 and third 30. The fourth will be a dismissal from the class with a grade of F. At the end the course, a student who displays an understanding of minerals at the level of 90% of the total point will be awarded an A; 80-89% a B, and 70-79% a C. A student who shows minimal knowledge gain will be given a D and no knowledge gain, an F. The grade will be based on exam scores (70%), report grades (20%), and class participation in discussion (10%). Grade:

7. Literature Critique During the course we will review papers that represent contributions to the basic literature of mineral nutrition. We will discuss the papers in class in a Journal Club style atmosphere. This means the instructor will lead a discussion of the paper’s content and call on students to answer specific questions or offer opinions. Students will be encourage to think critically, to weigh evidence, and to agree or disagree with the conclusions. Each student will then come up with his/hers own “take home”, which in one sentence, summarizes the contribution of the paper and stays as a lasting

8. WHERE TO BEGIN What is a Biomineral? Key words in the definition Chemical element or group of elements, mainly in ionic form Inorganic, i.e., possessing no carbon in its structure Classify a Mineral based on Nutrition Essential to vital functions, only source is the diet Functions cannot be duplicated by organic nutrients Two nutritional classifications based on occurrence Macro Micro or Trace

9. 3 Categories based on Chemistry and appearance Metal ions Metalloids Complexes 2 Categories based on impact Toxic Non-toxic

10. Questions to Ponder Are minerals essential? Some are Can we synthesize minerals? Some can be Both Do minerals function alone or in complexes? Are minerals bound to proteins? Some are Some do Do minerals function with enzymes? Do minerals function with hormones? Some do Some can Can minerals control genetic expression? Some can Can minerals control tissue integrity? No Are dietary minerals dependent only on animals sources?

11. Discuss the accuracies and inaccuracies of this Web Wisdom 1. Minerals are elements that originate in the Earth and cannot be made by living organisms. 2. For years the supplement market has been dominated by vitamins, but vitamins and amino acids are useless without minerals. 3. Minerals are needed to maintain the delicate cellular fluid balance, to form bone and blood cells, to provide for electrochemical nerve activity, and to regulate muscle tone and activity (including organ muscles like the heart, stomach, liver, etc.) 4. Minerals that come from plant sources are the best source. After all, humans like all other animals, were created to eat plants, not soil! 5. In order for minerals to be properly absorbed, they need to be acidic. When we consume inorganic minerals which are always quite alkaline, the body must attempt to acidify them for absorption.

12. Course Syllabus Introduction Chemistry periodic table and valence states transition metal chemistry Lewis acids and bases Biochemistry-Enzymes metal activated vs metalloenzymes geometry of metal complexes Nutrition Nutritional priorities Bioavailability Metal Interactions Physiology-Absorption and transport protein dependent membrane transporters chaperones

13. Metals and genetic regulation Mineral transcription factors Transacting elements Studies in yeast Experimental approaches Balanced diets Semipurified diets Intervention Criteria Biomarkers Isotopes Symptoms of mineral deficiencies Minerals and hormones Mineral-related diseases Individual Macrominerals Individual trace minerals

14. Organization of On-line textbook Chapter 1. Introduction to Minerals. • Definitions • Minerals as chemicals • Distinction between macro- and microminerals • Historical background • Mineral complexes • Nutritional perspective Chapter 2. Chemical Properties. I. General a. Chemical properties befitting function and behavior of minerals • Valance • Water solubility • Oxidation/reduction • Coordination geometry • Interaction with ligands

15. Organization of On-line textbook (Page 2) Chapter 3. Chemical properties. II. Electronic Structure of Minerals • Quantum theory of atomic structure • 1) ionization and valence • 2) Orbital shape • b. 3d transition metals • 1) orbital splitting • 2) ligand effects • 3) high spin/low spin states • c. Application to minerals Chapter 4. Biochemical properties • Biominerals • Minerals in pathways • Minerals as enzyme cofactors • 1) Metalloenzymes vs metal-activated • 2) Metalloproteins • Biomineralization • Zinc as a cofactor • Bone

16. Chapter 4 Biochemical Properties (cont.) g. Biochemical forms of iron h. Biochemical forms of copper i. Selenium and Iodine Chapter 5. Intestinal Absorption • General principles • Absorption of macromineral • Sodium • Potassium • Calcium • Magnesium and phosphate • Absorption of microminerals • Iron • Zinc • Copper • Selenium

17. Chapter 6. Post absorption and assimilation • Overall perspective • 1) rules governing transport and delivery • Membrane penetration • 1) simple diffusion • 2) facilitated diffusion • 3) active transport • 4) receptor-mediated endocytosis • Intracellular transport • 1) intracellular ligands • 2) chaperones for copper • d. Bioavailability • 1) key organs • 3) calculation of

18. Chapter 7. Nutritional Properties of Minerals • Assessing nutritional status • 1) balance • 2) clinical approaches • 3) standards of optimal uptake • Assessing mineral status • 1) body stores • 2) overt response to intake • 3) functional assays • 4) reversing deficiencies • Biomarkers: application and limitations • Assessing adequacy and risk of toxicity • 1) risk of excess • 2) assessing bioavailability